YOUR E-MAIL ALERTS

(CNN) -- Dennis Hwang may be the most famous unknown artist in the world -- his work doesn't hang in galleries or museums, but it's been viewed hundreds of millions of times.

The 28-year-old webmaster designs the whimsical logos that decorate Google.com's otherwise Spartan Web site on special occasions.

"It's always a fun kind of challenge to incorporate the logo into the design. Over the years, just because I kind of push myself to use different types of design if I can," Hwang said. (Have a look at Hwangs's Google logos)

He has been manipulating the six letters in the Google name into shamrocks, fireworks, hearts and goblins since shortly after he got an internship there in 2000. Company founders Larry Page and Sergey Brin found out that he was an art major in college.

"They said 'Hey Dennis, why don't you give this a shot,' and I've been doing it ever since," he said.

Now he's in charge of all Google's webmasters, and designing the logos is only about 20 percent of his job -- but that doesn't mean it's not a lot of work. Hwang said he had to do a string of all-nighters after he had what he called his "brilliant" idea to do individual designs for each of the 32 teams in this year's World Cup soccer tournament.

The logos link to Google search results about the topic, which can drive a lot of traffic to unsuspecting sites.

"Sometimes we unfortunately take some sites down, so we have to cycle through different search queries midday," he said. "But, yeah, it's kind of the fun aspect of it that users can do more research about a topic or find out more about it on their own if they're not as familiar about what we're recognizing."

John Malyon, president of the online art guide Artcyclopedia.com, said his site got a huge surge in traffic in April when Google featured Spanish surrealist painter Joan Miro. He said he got tens of thousands of extra clicks.

"It didn't cause any server problems or anything. It just took me a while to track down what was happening," Malyon said. "You sort of come in, you turn on your server and look at your stats and they're wildly inflated, so you then have to do some detective work."

Malyon said most of the traffic appeared to be "curiosity clicks" -- people who were more interested in the logo than in the artist's work. He said the surge probably didn't help his business much, but he appreciated the interest.

"I'm quite happy, and every webmaster in the world is happy to have as many people as possible see their babies, but it's not the most targeted traffic in the world," he said.

Hwang said users e-mail from all over the world to praise the designs or petition for new ones.

Hwang said they did a logo for the Persian New Year after a huge online campaign and that the National Library Day design was very popular.

"That one was a huge hit among librarians across the whole country," he said. They even sent me library-related cool toys and hats things like that. One was even a librarian action figure with 'shushing action' so that was really funny."

He said he meets a few times a year with a small group of Google staffers to decide which events to cover.

"We talk about interesting holidays that are coming up, or various international holidays or any current events or news events that we think are cool and geeky or 'Google-y' in some sense and then we just sort of give it a go," he said.

Hwang said his favorite was the birthday series honoring Michelangelo, Picasso, Van Gogh and other famous artists.

"Having been a student of art history for a long time those are a little bit more personal," Hwang said. "Of course, trying to mimic the style of a master is always difficult and humbling, so it does take a lot more time to do those, but it's also a lot more fun."

But, like any proud parent, he would not say which one was his favorite.

"If you had me picking just one, I don't think I could. They're just all kind of special in their own little way."